You get to go backstage with one of my favorite bands. They were the band of my time, pearl jam. They sold over 60 million records. A career spanning over two decades. Latest album, "lightning bolt," number one all the way around the world. I got to go to brooklyn and sit DOWN WITH mike McCready before another sold-out show and a great cause. Take a look. &#9834; they're one of the most popular bands in the world. And have been more than 20 years. They are, as ever, alive. &#9834; I'm still alive &#9834; outpacing so many of their rock contemporaries. And today, they have done it again. &#9834; delivering a "lightning bolt." To their massive and devout fan base. It's already gone number one in 56 countries. I think my favorite is the white falcon over there. Beautiful. Reporter: Fly, falcon, fly. Look at that. Pretty cool-looking. Reporter: Beautiful. I'll use that tonight. Reporter: I came of age with pearl jam. They're the band I gave my soul to. And this is lead guitarist mike McCREADY, WHO INVITED ME FOR A Rare look backstage. What are you playing right now? This is an s.G., I think -- jeff tweedy model. I love the color of it. Reporter: Is it -- will you -- I just got it today. I don't know. Reporter: What were you just playing right there? I was just making stuff up. Reporter: Just making stuff up. At the barclays center in brooklyn, pearl jam here for two sold-out shows. You've known each other over 20 years. How do you classify the relationship between the core group? We're all brothers, first, i think. Businessmen and friends and we love each other. And we fight. And we have problems. But we have to -- I think we respect each other enough, hopefully, that we'll -- you have to open lines of communication. And we're still working on that. &#9834; Reporter: Mccready, on the surface, naturally cool, almost imfallible, to a global legion of pearl jam fans. But what you might not know is he has been fighting a very private battle in his personal life, crohn's disease, which does as inflammation in his digest ive system. That has shadowed my existence since I was 21. I have to be able to create. Work out. Talk to other people who have it. Reporter: Other people like molly roberts and josh silverman, two young crohn's sufferers and fans. Turns out molly, a budding guitarist, is meeting her idol. I'm doing a pearl jam show, and soundgarden. Awesome. Awesome. Reporter: And this night, she's 1 of more than 18,000 pearl jam fanatics, taking in a 3-hour extravaganza. Does it feel like the first time every time? The exhilaration feels like the first time every time. The exhilaration and the energy, of it, feels unlike anything I've ever felt. Reporter: Pearl jam, showing us all, they can still bring the house down. It's great when your heroes are good people, too. mike McCready, whose work with the crohn's and colitis foundation, is just one example. I know you did. "Lightning bolt," the new kitchen! What's next?

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